The great fuel consumption poll

[RoyMacDonald]

Originally Posted by id5

Because it has nothing to measure the size of the wheels with, it only has the ABS rotation sensor.

So how does it detect that the tyre has changed size?

[id5]

Originally Posted by RoyMacDonald

So how does it detect that the tyre has changed size?

It cannot, which is the point I have been stating in this thread.

[emjga]

Originally Posted by simonjedrake

Also it needs to be CLEAR that this poll applies only to XC60 models as other forum members reading "Unread" posts may not notice that this thread originates in the XC60 forum......................

The forum is titled "S60 '10- / V60 '11- / XC60 '08- General Forum for the Volvo x60 Series of cars"

Hence you will get S60 owners in this forum as well.

[Craigy]

Originally Posted by emjga

The forum is titled "S60 '10- / V60 '11- / XC60 '08- General Forum for the Volvo x60 Series of cars"

Hence you will get S60 owners in this forum as well.

As well as V60 owners too.........This place does rather feel like an xc60 forum most of the time, they are becoming rather common.

[wimorrison]

Originally Posted by emjga

The forum is titled "S60 '10- / V60 '11- / XC60 '08- General Forum for the Volvo x60 Series of cars"

Hence you will get S60 owners in this forum as well.

Originally Posted by Craigy

As well as V60 owners too.........This place does rather feel like an xc60 forum most of the time, they are becoming rather common.

Only recently changed to allow other variants of the platform, used to be XC60 on its own, and before that the XC60 was in the XC90 forum.

This thread started without the V60 and s60

[RoyMacDonald]

Originally Posted by id5

It cannot, which is the point I have been stating in this thread.

Then how is it detecting that the tyre pressure are low with the ordinary tyre pressure monitor that does not use the special valves or anything inside the tyre?

And why does the handbook say the computer needs to recalibrate the tyres when the tyres or pressures are changed?

[RoyMacDonald]

Originally Posted by wimorrison

Only recently changed to allow other variants of the platform, used to be XC60 on its own, and before that the XC60 was in the XC90 forum.

This thread started without the V60 and s60

They are fairly similar I guess, so there is some logic to it, but unfortunately the mpg is the area that is most affected by the different drive systems and body shapes. So not good for the poll.

[GMcL]

Originally Posted by RoyMacDonald

Then how is it detecting that the tyre pressure are low with the ordinary tyre pressure monitor that does not use the special valves or anything inside the tyre?

And why does the handbook say the computer needs to recalibrate the tyres when the tyres or pressures are changed?

There are two types of TPMS monitor.

One is the recent valve but the earlier system which is making a comeback is using the abs ring to measure rotation speed.

If a tyre is deflated then it rotates at a different speed to the other tyres.

It takes a few miles to calibrate as the tyre warms up but after 10 minutes/miles it then can detect if one wheel is not within the parameters set by the other three.

[RoyMacDonald]

Originally Posted by GMcL

There are two types of TPMS monitor.

One is the recent valve but the earlier system which is making a comeback is using the abs ring to measure rotation speed.

If a tyre is deflated then it rotates at a different speed to the other tyres.

It takes a few miles to calibrate as the tyre warms up but after 10 minutes/miles it then can detect if one wheel is not within the parameters set by the other three.

Thanks. Someone on the forum said it was pretty sensitive at detecting the difference in pressures.

When I fitted different size tyres on mine I expected the speedo to be more accurate by the amount of increase size percentage. However I did not know to ask the dealer not to recalibrate the tyres and when I checked the speedo error it was exactly the same as it was with the original tyres on. Do you think Volvo have programed a standard rotation speed into the computer that the computer measures against? This is on the 2015 model.

[GMcL]

I can't answer for Volvo. If you have a TPMS system fitted then it makes sense to speak with your dealer to find out what you have: Valve vs abs ring speed.

I'm just relieved we managed to get my wife's car with a certification date before TPMS was mandatory. By the time we both need new cars this whole thing should be sorted.

I'd love a new S60 with a proper under floor spare wheel and a D4 engine with 230+PS from tuners. I've still got my bike if I want real speed.